• Title/Summary/Keyword: structural materials

Search Result 5,861, Processing Time 0.034 seconds

Similarities of Scaritoxin to Ciguatoxin on the Chromatographic Behaviours (Scaritoxin과 Ciguatoxin의 크로마토그라피상에서의 몇가지 유사성)

  • Joh, Yong-Goe;Scheuer, Paul J.
    • Korean Journal of Food Science and Technology
    • /
    • v.17 no.2
    • /
    • pp.121-127
    • /
    • 1985
  • In studying the structural work on ciguatoxin, parrot fish collected were identified as Scarus sordidus, S. frenatus, S. scaber and S. pectarlis, in which only S. sordidus contained toxic materials. Crude toxins obtained by silicic acid column chromatography, could be separated on a DEAE-cellulose column into two fractions, ST-1(less polar) and ST-2(polar) eluted with chloroform and chloroform-methanol(1:1). Furthermore ST-1 could be changed into ST-2 by repeated chromatography on DEAE-cellulose. Rf values of ST-1 and ST-2 were 0.60-0.75 and 0.30-0.54 on TLC coated with silica gel 60F-254 developed by chloroform-methanol-water-acetic acid (90:9.5:0.2:0.3) mixture. The peaks of ST-1 and ST-2 were not observed on each HPLC chromatogram at low sensitivity(2X), but by bioassay they were detected in the fraction of 24-27ml(less polar toxin, 120ng) and 22-27 ml (polar toxin, 150 ng). Less polar ciguatoxin from morey eel viscera also showed its peak in the same elution volume(25ml). Being subjected to chromatography on basic aluminum oxide (activity grade I) or to alkaline treatment, followed by basic aluminum oxide (activity grade I) chromatography ST-1 toxin was remarkably converted into the polar toxic component supposed to be polar ciguatoxin in both cases. In the latter case, approximately 74% of the residual toxicity was changed into the polar component, accompanied by about 50% loss of the initial toxicity. More than 26% of ST-2 toxicity was transformed into the less polar toxic component supposed to be less polar ciguatoxin on a deactivated aluminum oxide (activity grade V) column.

  • PDF

A Study on the Characteristics of Humic Materials Extracted from Decomposing Plant Residues -I. Chemical Properties of Humic Acids from Plant Residues Characterized by IR Spectra (식물성(植物性) 유기물질(有機物質)의 부숙과정중(腐熟過程中) 부식특성(腐植特性)에 관(關)한 연구(硏究) -1. 분광분석(分光分析)에 의(依)한 식물잔해(植物殘骸) 부식산(腐植酸)의 화학적(化學的) 성질규명(性質糾明))

  • Kim, Jeong-Je;Shin, Young-Oh
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.20 no.3
    • /
    • pp.251-259
    • /
    • 1987
  • Humic acids extracted from decomposing plant residues were characterized by infrared(IR) spectra. The IR spectra were further interpreted by chemical analyses for oxygen-containing functional groups such as carboxyl, phenolic, alcoholic, carbonyl, and quinionic groups. 1. The IR spectra obtained in this study were divied into three categories: spectra of humic acids from grain crop straws of rice, barley, wheat and rye produced Type I, while that from wild grass hay yielded Type II, and those from forest tree litter of the deciduous and conifers were led to give Type III. 2. There were no significant changes in the absorption bands observed among humic acids extracted at various stages of decomposition of a given Plant material. 3. The absorption band at about $3,430cm^{-1}$ represents the presence of hydrogen-bonded hydroxyl groups, phenolic-OH groups being the major component. 4. A close relationship was found between the total acidity and the content of phenolic-OH groups of humic acids. The content of carboxyl groups maintains a direct relationship with the content of total hydroxyl groups, and such a close relationship also exists between the content of alcoholic hydroxyls and that of total hydroxyl groups. 5. Overlapping of the absorption bands of carbonyl groups and quinones renders it difficult to make differentiation between the two. 6. A variety of non-armoatic cyclic hydrocarbons appears to be a structural component as evidenced by a sharp absorption peak near $995-1000cm^{-1}$.

  • PDF

Development of the Glandular Trichomes in Trapping Leaves of Drosera Species (끈끈이주걱속 점착식 포충엽의 분비모 발달)

  • Lee, Hye-Jin;Kim, In-Sun
    • Applied Microscopy
    • /
    • v.39 no.1
    • /
    • pp.57-64
    • /
    • 2009
  • The trapping leaves of Drosera capture insects by secreting sticky mucilage from numerous glandular trichomes (GTs) that are developed on the leaf epidermis. The present study examines and compares the structural features of those trichomes in Drosera binata and D. pygmy with the use of light and electron microscopy. The study focuses primarily on the development and differentiation pattern of the GTs during growth. Upon examination, the upper and lower epidermis were readily distinguishable by the features of GTs in developing leaves. In particular, the GTs were dense in the upper epidermis and along the leaf margin. In D. binata, the capitate GTs with elongated stalk and sessile peltate GTs were found most commonly, whereas only capitate GTs with varying degrees of the stalk length were observed in D. pygmy. Up to ca. $2.2{\sim}3.4\;mm$ long capitate GTs were seen in the leaf margins of D. binata and ca. $3.7{\sim}4.2\;mm$ long GTs having racket-like head with adaxial hemispheric structures, otherwise known as tentacles, were noted in the leaf margin of D. pygmy. The peltate GTs were found to be distributed in the lower epidermis of D. binata. In both species, head cells were dense with cytoplasm containing high numbers of Golgi bodies, ER, mitochondria and small vesicles. Secretory materials accumulated within numerous small vacuoles, then fused together to form a single large vacuole, which serves as a secretory cavity. Flection movement of the marginal GTs and leaf blade GTs, and increased mucilage secretion from the head cells upon contact with prey during the capturing process are considered to be major factors in their active insectivorous mechanism. The findings of this study will be useful in comparisons to similar findings in other species that form adhesive trapping leaves, such as Drosophyllum or Pinguicula., further contributing a better understanding of the function and structure of the trapping leaves of carnivorous plants.

Clinical Result of Layered Suture Bridge Technique in Arthroscopic Repair for Delaminated Rotator Cuff Tear (회전근 개 층간 분리 파열에서 관절경을 이용한 층상 교량형 봉합술의 임상 결과)

  • Choi, Eui-Sung;Park, Kyoung-Jin;Kim, Yong-Min;Kim, Dong-Soo;Shon, Hyun-Chul;Cho, Byung-Ki;Park, Ji-Kang;Kim, Dong-Whan;Keum, Sang-Wook;Cha, Jung-Kwon
    • Clinics in Shoulder and Elbow
    • /
    • v.16 no.2
    • /
    • pp.84-93
    • /
    • 2013
  • Purpose: The purpose of this study was to evaluate the repair integrity and clinical outcomes of delaminated tears following arthroscopic layered suture bridge rotator cuff repair in a prospective fashion. Materials and Methods: A consecutive series of 67 patients with delaminated rotator cuff tears who underwent surgery using the arthroscopic Layered Suture Bridge Technique were followed prospectively. Of 67 shoulders, 26 patients were male and 40 patients were female (one patient had bilateral tears); the mean age was 58.8(40~76) years. The clinical evaluation was performed according to ASES, UCLA, and KSS (Korea Shoulder Scoring System) scores with an average follow up period of 33 months. Repair integrity was estimated using MRI, which was performed six months postoperatively. Results: The average clinical outcome in ASES, UCLA, and KSS scores showed significant improvement at the time of the final follow-up compared to preoperatively, from 50.2 to 92.3, 15 to 31.3, and 54.4 to 90.7, respectively (p<0.001 for all scores). Follow up by MRI showed that 16 shoulders had a type-I; 14, a type-II; five, a type-III; two, a type-IV; one, a type-V re-tear. The overall rate of re-tear (types IV and V) was 7.9%. Conclusion: Use of the Arthroscopic Layered Suture Bridge Technique can result in improved functional and structural outcome in cases of delaminated rotator cuff tear.

Outcome of Preimplantation Genetic Diagnosis for Chromosome Aneuploidy and Genetic Disease (유전질환 및 염색체 이상의 예방을 위한 착상전 유전진단의 결과)

  • Kim, Jin-Yeong;Lim, Chun-Kyu;Song, In-Ok;Yoo, Keun-Jai;Yang, Kwang-Moon;Han, Kuk-Sun;Hur, Kuol;Song, Ji-Hong;Jun, Jin-Hyun;Min, Dong-Mi;Park, So-Yeon;Jun, Jong-Young;Koong, Mi-Kyoung;Kang, Inn-Soo
    • Clinical and Experimental Reproductive Medicine
    • /
    • v.29 no.4
    • /
    • pp.269-278
    • /
    • 2002
  • Objective s: Chromosome aneuploidy is associated with recurrent abortion and congenital anomaly and genetic diseases occur repeatedly in the specific families. Preimplantation genetic diagnosis (PGD) can prevent aneuploidy or genetic disease by selecting normal embryos before implantation and is an alternative to prenatal diagnosis. The aim of this study is to assess the outcome of PGD cycles by using FISH or PCR, and to determine the clinical usefulness and values in patients with risk of chromosomal aneuploidy or genetic disease. Materials and Methods: From 1995 to Apr. 2001, a total of 108 PGD cycles in 65 patients with poor reproductive outcome were analyzed. The indications of PGD were translocation (n=49), inversion (n=2), aneuploidy screening (n=7), Duchenne muscular dystrophy (n=5) and spinal muscular atrophy (n=2). PGD was applied due to the history of recurrent abortion, previous birth of affected child or risk of aneuploidy related to sex chromosome aneuploidy or old age. Blastomere biopsy was performed in 6$\sim$10 cell stage embryo after IVF with ICSI. In the single blastomere, chromosome aneuploidy was diagnosed by using FISH and PCR was performed for the diagnosis of exon deletion in DMD or SMA. Results: The FISH or PCR amplification was successful in 94.3% of biopsied blastomeres. The rate of transferable balanced emb ryos was 24.0% in the chromosome translocation and inversion, 57.1% for the DMD and SMA, and 28.8% for the aneuploidy screening. Overall hCG positive rate per transfer was 17.8% (18/101) and clinical pregnancy rate was 13.9% (14/101) (11 term pregnancy, 3 abortion, and 4 biochemical pregnancy). The clinical pregnancy rate of translocation and inversion was 12.9% (11/85) and abortion rate was 27.3% (3/11). In the DMD and SMA, the clinical pregnancy rate was 33.3% (3/9) and all delivered at term. The PGD results were confirmed by amniocentesis and were correct. When the embryos developed to compaction or morula, the pregnancy rate was higher (32%) than that of the cases without compaction (7.2%, p<0.01). Conclusions: PGD by using FISH or PCR is useful to get n ormal pregnancy by reducing spontaneous abortion associated with chromosome aneuploidy in the patients with structural chromosome aberration or risk of aneuploidy and can prevent genetic disease prior to implantation.

Submicroscopy of Forest Soils (kandiustults) Derived from Granite in Southern Part of Korea (우리나라 남부지역(南部地域) 화강암질(花崗巖質) 삼림토양(森林土壤)의 SEM과 TEM에 의한 관찰(觀察))

  • Cho, Hi Doo;An, Ki Wan
    • Journal of Korean Society of Forest Science
    • /
    • v.90 no.5
    • /
    • pp.608-618
    • /
    • 2001
  • To understand the weathering processes of the soil by submicroscopic method is very important to realize the properties of the soils. In this study soil formation processes show every steps to the changes in chemical and mechanical properties and the submicroscopic characteristics of soil weathering on the profiles of forest soils derived from granite in southern part of Korea. Fecal pellets(SEM) are given a full detail of the positive activities of the forest soil animals; mainly invertebrates in the O horizon and the E horizon. External shapes of fecal pellets have been divided into five groups : spherical, ellipsoidal, cylindrical, platy and threadlike. But doughnutlike form of fecal pellets is observed in this study. The soluble and suspended materials in the soils move downwards by percolation from the A horizon to the B or the BC horizons, and result in the illuviation cutans(SEM) on the ped surface of the lower horizon and deposited stack of kaolinite. Illuviated cutans are deposited on the ped surface even in the depth of 312cm in the BC horizon as well as the Bt horizon and comprise of fine silt, coarse clay and fine clay. A lot of halloysites are observed on the cutan surface. Halloysite formation from feldspars has been well known but a lot of hallyosite formation are observed in this study. The formation were predicted by Jackson(1962), inferred by Wada and Kakuto(1983a, b) and proved evidently by Cho and Mermut(1992a, b). This also suggests that halloysites in the soils derived from granite are formed a lot from ferruginous chlorites. The release of Fe from the chlorite structure are significant pedogenic processes and newly formed Fe oxides imparted a red color to the soils. The iron oxides particles, which are ejected and recrystalized, aggregate thickly on the edge of the ferruginous chlorites, and this indicates the release of structural Fe from weathered chlorites. Hematites and goethites are frequent in the fine clay in this soils.

  • PDF

The Result of Bone Grafting for Fibrous Dysplasia (섬유성 골 이형성증에서 시행한 골 이식술의 결과 분석)

  • Jeong, Won-Ju;Kim, Tae-Seong;Cho, Hwan-Seong;Yoon, Jong-Pil;Park, Il-Hyung
    • The Journal of the Korean bone and joint tumor society
    • /
    • v.20 no.2
    • /
    • pp.74-79
    • /
    • 2014
  • Purpose: Fibrous dysplasia is related to the mutation of gene encoding the alpha-subunit of a signal-transducing G-protein and has variable clinical course. Operation can be performed to prevent functional disorder or structural deformity. After curettage, autologous bone graft were used to fill the defects after curettage. The aim of this study is to compare the result of autogenous cancellous bone grafting and allogenic bone grafting for fibrous dysplasia. Materials and Methods: Among the patients who visit our hospital during the period of April, 1997 to October, 2013, we selected 34 patients who diagnosed fibrous dysplasia and visited our clinic over 1 year. There were 13 males and 21 females. Average age was 26.4 (range 2 to 57) years old. Autogenous bone graft (group I) in 5 cases, Non-autogenous bone graft (group II) in 30 cases. Iliac bone is used in all cases of autogenous bone graft. There were no significant difference in age, follow-up period, preoperational laboratory finding between two groups. Radiographic image was done to evaluate the recurrence of fibrous dysplasia or secondary degeneration. Results: There were four cases in recurrence (group I: 1 case, group II: 3 cases, p=0.554). In all recurrent cases, reoperations were done using curettage and autogenous iliac bone graft. There was no re-recurrence after reoperation. One case of secondary aneurysmal bone cyst was confirmed (group II) and 1 cases of pathologic fractures had developed (group I: 0 case, group II: 1 cases, p=0.559). No malignant change occurred. Conclusion: There were no significant difference between autogenous bone graft group and non-autogenous bone graft group. Our result suggested that autogenous bone graft seems to be good method to treat fibrous dysplasia, in the case of small volume of tumor lesion or non-weight bearing portion.

The Bone Regenerative Effects of Chitosan on the Calvarial Critical Size Defectin Sprague Dawley Rats (백서 두개골 결손부에서 키토산의 골조직 재생 유도 효과)

  • Jung, Ui-Won;Suh, Jong-Jin;Choi, Seong-Ho;Choi, Kyoo-Sung;Chai, Jung-Kiu;Kim, Chong-Kwan
    • Journal of Periodontal and Implant Science
    • /
    • v.30 no.4
    • /
    • pp.851-870
    • /
    • 2000
  • The major goals of periodontal therapy is the functional regeneration of periodontal supporting structures already destructed by periodontal disease as well as the reduction of signs and symptoms of progressive periodontal disease. There have been many efforts to develop materials and therapeutic methods to promote periodontal wound healing. There have been increasing interest on the chitosan made by chitin. Chitin is second only to cellulose as the most abundant natural biopolymer. It is a structural component of the exoskeleton of invertebrates(e.g., shrimp, crabs, lobsters), of the cell wall of fungi, and of the cuticle of insects. Chitosan is a derivative of chitin made by deacetylation of side chains. Many experiments using chitosan in various animal models have proven its beneficial effects. The aim of this study is to evaluate the osteogenesis of chitosan on the calvarial critical size defect in Sprague Dawley rats. An 8 mm surgical defect was produced with a trephine bur in the area of the midsagittal suture. The rats were divided into two groups: Untreated control group versus experimental group with 50mg of soluble chitosan gel. The animals were sacrificed at 2, 4 and 8 weeks after surgical procedure. The specimens were examined by histologic, histomorphometric and radiodensitometric analyses. The results are as follows: 1. The length of newly formed bone in the defects was $102.91{\pm}25.46{\mu}m$, $219.46{\pm}97.81{\mu}m$ at the 2 weeks, $130.95{\pm}39.24{\mu}m$, $212.39{\pm}89.22{\mu}m$ at the 4 weeks, $181.53{\pm}76.35{\mu}m$ and $257.12{\pm}51.22{\mu}m$ at the 8 weeks in the control group and experimental group respectively. At all periods, the means of experimental group was greater than those of control group. But, there was no statistically significant difference between the two groups. 2. The area of newly formed bone in the defects was $2962.06{\pm}1284.48{\mu}m^2$, $5194.88{\pm}1247.88{\mu}m^2$ at the 2 weeks, $5103.25{\pm}1375.88{\mu}m^2$, $7751.43{\pm}2228.20{\mu}m^2$ at the 4 weeks and $8046.20{\pm}818.99{\mu}m^2$, $15578.57{\pm}5606.55{\mu}m^2$ at the 8 weeks in the control group and experimental group respectively. At all periods, the means of experimental group was greater than those of control group. The experimental group showed statistically significant difference to the control group at the 2 and 8 weeks. 3. The density of newly formed bone in the defects was $14.26{\pm}6.33%$, $27.91{\pm}6.65%$ at the 2 weeks, $20.06{\pm}9.07%$, $27.86{\pm}8.20%$ at the 4 weeks and $22.99{\pm}3.76%$, $32.17{\pm}6.38%$ at the 8 weeks in the control group and experimental group respectively. At all periods, the means of experimental group was greater than those of control group. The experimental group showed statistically significant difference to the control group at the 2 and 8 weeks. These results suggest that the use of chitosan on the calvarial defects in rats has significant effect on the regeneration of bone tissue in itself

  • PDF

Development of a Korean Standard Structural Brain Template in Cognitive Normals and Patients with Mild Cognitive Impairment and Alzheimer's Disease (정상노인 및 경도인지장애 및 알츠하이머성 치매 환자에서의 한국인 뇌 구조영상 표준판 개발)

  • Kim, Min-Ji;Jahng, Geon-Ho;Lee, Hack-Young;Kim, Sun-Mi;Ryu, Chang-Woo;Shin, Won-Chul;Lee, Soo-Yeol
    • Investigative Magnetic Resonance Imaging
    • /
    • v.14 no.2
    • /
    • pp.103-114
    • /
    • 2010
  • Purpose : To generate a Korean specific brain template, especially in patients with Alzheimer's disease (AD) by optimizing the voxel-based analysis. Materials and Methods : Three-dimensional T1-weighted images were obtained from 123 subjects who were 43 cognitively normal subjects and patients with 44 mild cognitive impairment (MCI) and 36 AD. The template and the corresponding aprior maps were created by using the matched pairs approach with considering differences of age, gender and differential diagnosis (DDX). We measured several characteristics in both our and the MNI templates, including in the ventricle size. Also, the fractions of gray matter and white matter voxels normalized by the total intracranial were evaluated. Results : The high resolution template and the corresponding aprior maps of gray matter, white matter (WM) and CSF were created with the voxel-size of $1{\times}1{\times}1\;mm$. Mean distance measures and the ventricle sizes differed between two templates. Our brain template had less gray matter and white matter areas than the MNI template. There were volume differences more in gray matter than in white matter. Conclusion : Gray matter and/or white matter integrity studies in populations of Korean elderly and patients with AD are needed to investigate with this template.

THE EFFECT OF RESORBABLE MEMBRANE ON BONE REGENERATION IN CALVARIAL DEFECTS OF RATS (백서의 두개골 결손부에서 탈단백우골 이식 시 흡수성악의 효과)

  • Park, Young-Jun;Choi, Guen-Ho;Jang, Jung-Rok;Jung, Seung-Gon;Kim, Young-Joon;Yu, Min-Gi;Kook, Min-Suk;Oh, Hee-Kyun;Ryu, Sun-Youl;Park, Hong-Ju
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • v.31 no.5
    • /
    • pp.365-374
    • /
    • 2009
  • Purpose : This research evaluates the effect of the use of absorbable membrane barrier with deproteinized bovine bone (Bio-$Oss^{(R)}$, Switzerland) on bone healing in surgically created critical-sized defects in rat calvaria. Materials and Methods : Two standardized transosseous circular calvarial defects (5 mm in diameter) are made in each calvarium of 30 rats. These rats are divided into negative control group(n=15), positive control group(n=15) and two experimental groups(n=15). In the negative control group, defects are only filled with blood clots. In the positive control group, defects are filled with autogenous bone obtained from calvarium; in the experimental group 1, defects are filled with deproteinized bovine bone; and in the experimental group 2, defects are filled with deproteinized bovine bone with absorbable membrane. At the postoperative 1 week, 3 weeks. and 6 weeks, clinical. histologic and histomorphometric evaluations of the defects are performed. Results : 1. The grafted bone without membrane in the calvarial bone defect was scattered but, the grafted bone with membrane was stable. 2. $BioMesh^{(R)}$ membrane was absorbed beginning at 3 weeks, and was absorbed considerably at 6 weeks while maintaining the structural form of the membrane. 3. The use of membrane blocked soft tissue invasion. 4. In histomorphometric analysis. it showed the greatest amount of new bone formation in the positive control group. The amount of new bone formation was greater in the experimental group 2 than experimental group 1. At 6 weeks. the amount of new bone formation was greater in the positive control group than experimental group l(p<0.005). Conclusion : These results suggest that membrane increase the stability of grafted bone and protects from soft tissue invasion, and the use of the membrane may promote new bone formation in deproteinized bovine bone graft area.